Coffee brewing apparatus



Feb. 26, 1963 H. HlLFxKER COFFEE BREWING APPARATUS Filed April 2o, 1961 VENTOR HANS H/F/KEK BZMMVM ATTORNEYS United States Patent d C 3,078,784 COFFEE BREWING APPARATUS Hans Hilliker, Kilchberg, Zurich, Switzerland, assgnor to Titcrma A.G., Schwanden, Glarus, Switzerland Filed Apr. 20, 1961, Ser. No. 104,307 Claims priority, application Switzerland Apr. 29, 1960 8 Claims. (Cl. 99282) This invention rela-tes to a coffee brewing apparatus which comprises a vessel for supplying hot water and a lil-ter vessel having a iloat for the automatic control of the water level in the filter vessel, whereby, owing to a slight overpressure within the water vessel, the hot water therein is automatically urged out of the vessel yand over the lloat regulating the water supply.

As an improvement of lthe apparatus described in my prior application Serial No. 860,937, the stability of the superposed vessels may be increased by lowering the centre of gravity of the hot water vessel. According to the invention, the vessel for preparing hot water iS so arranged that when placed upon the lilter vessel, it extends downwardly outside of and beyond the top of the lter vessel.

The hot water supply vessel suitably is formed hoodshaped, surrounding the top and side wall of the tlter vessel, whereby the water is heated in the annular downwardly extending portion. Advantageously the -aperture for vapour discharge, provided in the cover of the hot water supply vessel, is arranged so that it is located at a point remote of the water level. Boiling water is thus Iprevented from leaking through said aperture. The knob of the cover is formed so that it contains the opening for vapour discharge and is provided with a bayonet joint for securing the cover.

The counterpart of the bayonet joint is anchored in an upstanding column extending -from the bottom of the vessel for hot water preparation and carrying a water supply duct, as communication means vfrom the lowermost point of the vessel beyond the uppermost water level to the regulating member, said column is provided at its bottom end with a funnel-shaped water discharge opening -which forms :a valve seat for the regulating member land exerts a centering action upon the float.

According to a further development of the invention the toat itself may be vformed as valve body, in which case, for example, an upwardly extending bulged portion centrally larranged on the top of the float coacts with the valve seat. lDue to its particular outside dimensions the iloat is roughly centered in the lter vessel.

Furthermore, a thermostat may be mounted in a recess ot the hood-shaped water vessel, and this recess may be closed by the carrying handle of the vessel. The entire vessel thus lwill be constructed in waterproof manner.

'The parts which require cleaning, thus the lilter and the Ioat, are easily accessible. By combining different functions to be effected by single components of the apparatus, a ldevice results having a reduced number of parts capable of being produced at low cost.

The present invention will now be described in more detail with reference to the accompanying drawing i1- lustrating, by way of example, a vertical sectional view of -a preferred embodiment of the invention.

A ceramic coffee pot 1 supports a ceramic tilter vessel 2 on the top of which is supported a water vessel 3 by means of the end faces of three ribs 4 provided on the vessel 3. A resiliently yielding cover 5 having a gasket -6 is secured by a bayonet joint 7 provided on a rotatable knob 8 against -a counterpart 9 to tightly seal the vessel 3. The knob 8 is provided with a small Vapourdischarge aperture 10 for limiting the vapour pressure. The column =9 consists of two parts which have erle@ screw threads that when engaged clamp the central -portion of the vessel 3. The column l9 is lanchored in the vessel 3 `and carries va water tube 11. The column is Aalso provided with a central duct 20 communicating with the -tube 11 and provided at its bottom end with a funnel-shaped opening 12. A oat '13 floating on the coffee water 15 has a bulged Iboss 14 coacting as valve with the water discharge opening 12.

The vessel 3 is provided with electric heating means 17, |the heating current being controlled by means of a thermostat mounted in a recess 18 of the water vessel. The recess 18 is closed by `a handle 19. The handle 19 is so formed that it closes the recess 18 containing the thermostat 23.

The preparation of collec in the described device starts by iilling water into the hot Water preparing vessel 3. After the cover 5 has been closed by downwardly forcing and turning the knob 8, the electric supply cable 21 can be plugged in. Freshly ground coffee is then poured into a usual paper iilter 22 provided within the lilter vessel, the lloat 13 i-s inserted with the boss 14 at its top land the tlter vessel 2 is put upon the coffee pot 1.

The vessel 3 can then be placed upon the lilter vessel 2. Then the preparation of coffee proceeds automatically. The water heated by the heater 17 is brought to the boiling point. The 'vapour thereby developed generates pressure which is limited by the aperture 10 in the knob l8 and forces the hot Water through the water tube 11 and the duct 20 over the float 13 Iand upon the coffee powder -in the iilter vessel 2. The steam reaches the aperture 10 by the clearances in the bayonet joint 7. The lloat then maintains a predetermined water level in the lter vessel and regulates the supply of hot water by closing and opening the water discharge opening 16 of the duct 20. As soon as all the water has been forced out of the vessel 3, the thermostat in the recess 15 automatically shuts off the current supply. When all the water has been forced out of the vessel 3 the temperature rises in the entire vessel including the recess 18. The thermostat 23 opens and breaks the current supply. After the vessel 3 and the lter vessel 2 have been removed, the coffee is available in the pot 1.

I claim:

l. A coliee brewing apparatus comprising a lter vessel to be placed on a coffee pot, a water vessel removably mounted on said filter vessel, means for heating water in said water vessel, tubular means extending between said water vessel and said lilter vessel for supplying hot water from said lwater vessel to said lter vessel when said water is heated and steam pressure is buil-t up above said Water, -a float positioned in said filter vessel controlling the supply of hot water through said tubular means to said lter vessel, said water vessel having `a. -depending hollow annular skirt portion extending downwardly outside of and below the top of said filter vessel.

2. A coffee brewing Iapparatus according to claim l, wherein an aperture for steam discharge is located in said water vessel above the water level in said water vessel.

3. A coffee brewing apparatus according to claim 2, wherein said water vessel comprises a removable cover having a knob in which said aperture is located for limiting the steam pressure generated in said water vessel.

4. A coffee brewing apparatus according to claim 3, wherein a column is mounted in the bottom of said water vessel and said knob is secured at the middle of said cover by a bayonet joint against said column whereby the edge of said cover is urged against the edge of said water vessel -to provide a tight closure.

5. A coffee brewing apparatus according to claim 4, lwherein said tubular means supplying hot water to the aorsaa filter vessel opens into said column and is supported by wherin -said annular hollow skirt portion has a recess, a the lat-ter. thermostat located in said recess and Ia handle for said 6. A coffee brewing apparatus according `to claim 5, water vessel closes said recess. wherein said column has a. water discharge opening of funnel shape serving as a valve seat for `said float. 5 References Cited in the me of this patent 7. A coffee brewing apparatus, according to claim 6, wherein the top side of said float is provided inrits cen- UNITED STATES PATENTS tre with a -bulged iboss having a spherically curved top 1,109,740 Dehn Sept. 8 1914 surface cooperating with said valve seat. 1,705,190 Shroyer Mal-- 19l 1929 8. A coffee brewing apparatus according `to claim 1, 10 

1. A COFFEE BREWING APPARATUS COMPRISING A FILTER VESSEL TO BE PLACED ON A COFFEE POT, A WATER VESSEL REMOVABLY MOUNTED ON SAID FILTER VESSEL, MEANS FOR HEATING WATER IN SAID WATER VESSEL, TUBULAR MEANS EXTENDING BETWEEN SAID WATER VESSEL AND SAID FILTER VESSEL FOR SUPPLYING HOT WATER FROM SAID WATER VESSEL TO SAID FILTER VESSEL WHEN SAID WATER IS HEATED AND STEAM PRESSURE IS BUILT UP ABOVE SAID WATER, A FLOAT POSITIONED IN SAID FILTER VESSEL CONTROLLING THE SUPPLY OF HOT WATER THROUGH SAID TUBULAR MEANS TO SAID FILTER VESSEL, SAID WATER VESSEL HAVING A DEPENDING HOLLOW ANNULAR SKIRT PORTION EXTENDING DOWNWARDLY OUTSIDE OF AND BELOW THE TOP OF SAID FILTER VESSEL. 